USB: CONFIG_USB_GADGET_DUALSPEED is not user-configurable

This patch (as1468) changes the Kconfig definition for
USB_GADGET_DUALSPEED.  This option is determined entirely by which
device controller drivers are to be built, through Select statements;
it does not need to be (and should not be) configurable by the user.

Also, the "default n" line is superfluous -- everything defaults to N.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/Kconfig

@@ -632,13 +632,10 @@ config USB_DUMMY_HCD
 
 endchoice
 
+# Selected by UDC drivers that support high-speed operation.
 config USB_GADGET_DUALSPEED
 	bool
 	depends on USB_GADGET
-	default n
-	help
-	  Means that gadget drivers should include extra descriptors
-	  and code to handle dual-speed controllers.
 
 #
 # USB Gadget Drivers